If you're going to hike in the snow, you'll probably want to wear your wool socks. Not only do they insulate your toes from the cold, but your socks will still do a good job if a little snow or slush gets into your boots. That same principle applies for insulating wall cavities in places where sheep's wool is plentifully available.

But a new technology promises to make lamb's wool an even more practical choice for the building industry, as U.S. manufacturer SayrCo prepares to introduce WEKA semi-rigid insulation panels to market. The product is essentially a wool-based interior sheetrock with some serious R-value and other environmental benefits.

Think of it as ‘sheeprock.'

Shear simplicity in production

The manufacturing process is rather simple and low-tech. Freshly shorn wool is thoroughly chopped, washed, and then mixed into a binder that includes quicklime and other natural ingredients designed to fortify the wool's natural fire, mold, and vermin resistance. The resulting slurry is then pressed into 4' x 8' or 4' x 12' sheets, air dried, and covered on both sides with the same type of heavy paper used in gypsum board.

The lightweight WEKA panels have an R-value of 6.5, and they can be mounted 3 deep on the indoor side of exterior walls to produce an R-19.5 assembly without stuffing any additional insulation into the cavities. As a result, builders can use 2 x 4 rather than 2 x 6 studs, and also eliminate the thermal bridging that is typical when conventional batts are used.

Installing WEKA panels is no more complicated than installing drywall. The panels use the same tape, mud, fasteners, and adhesives as conventional sheetrock while providing drywall and insulation in a single step.

Environmental advantages

According to Christian Tasser, the developer of WEKA, a similar product has been used in Italy for 10 years, and it has proven thoroughly stable and free of any issues. From that experience, Tasser can point to an important IAQ benefit: stabilized sheep's wool can absorb up to 40 percent of its own weight in humidity and water content, and then release it when conditions dry out. “It takes the humidity out of the room, and at the same time it neutralizes any kind of unwanted fungi or pests,” he said. “The wool also controls any air contaminants such as formaldehyde by drawing it into the wool, and it stays there.”

In addition, Mike Peterpaul of SayrCo aims for high environmental standards on the manufacturing side. “We're working with sheep farms within a 100 mile radius of our plant,” he said. “The energy footprint to manufacture the product is very, very low. The wool is naturally dried after it's washed, the water will be recaptured, plus the whole process has a very low carbon footprint,” he said.

Peterpaul expects to start shipping WEKA in quantity by August or September, and he's looking to launch it through a network of 100-200 green oriented distributors. SayrCo intends to support the rollout with local advertising that draws builders, contractors, and consumers directly to those dealers.